Here's my advice for mining ....
1) Take more than one Collector Limpet Controller. At a minimum, have one limpet per small mining laser and three per medium mining laser.
2) Bind the Collector Limpets to the same button as the mining laser. This way, the collectors will automatically go out as soon as you start mining and will replenish themselves instantly when one of them dies. Put the prospector limpet controller on fire button number 2. You won't have to switch out firegroups ever.
3) Skip the small mining lasers if you have a choice. A medium mining laser is 3.5 times as fast but only takes twice the power draw. The optimal number of medium mining lasers depends on your Power Distributor: PD of 8 = 4 med lasers, PD of 6 or 7 = 3 med laser, for everyone else 2 is the most efficient. If you have to use small mining lasers, there's no need to use more than 2 unless you've engineer your PD for charge enhanced (or whatever it's called). [This is because all ships with a PD capable of handling more than 2 small mining lasers already have medium hardpoints so should be using medium mining lasers anyway]
4) Finally, the rating of your prospector limpet controller controls the number of fragments you get out of an asteroid. So go with A-rated ones if at all possible. If the 1A is all you can afford, stick with that until you can get a 3A or 5A (although I don't see much need for more than two limpets at a time.)
